title: Activity restriction among women with a short cervix.
abstract: OBJECTIVE
  To estimate determinants of and outcomes associated with activity restriction among women with a short cervix.
  
  
  METHODS
  This was a secondary analysis of a randomized trial of 17-α hydroxyprogesterone caproate for prevention of preterm birth among nulliparous women with singleton gestations and cervices less than 30 mm by midtrimester ultrasonography. Women were asked weekly whether they had been placed on pelvic, work, or nonwork rest. "Any activity restriction" was defined as being placed on any type of rest. Factors associated with any activity restriction were determined and the association between preterm birth and activity restriction was estimated with multivariable logistic regression.
  
  
  RESULTS
  Of the 657 women in the trial, 646 (98%) responded to questions regarding activity restriction. Two hundred fifty-two (39.0%) were placed on any activity restriction at a median of 23.9 weeks (interquartile range 22.6-27.9 weeks). Women on activity restriction were older, more likely to have private insurance, less likely to be Hispanic, had a shorter cervical length, and were more likely to have funneling and intra-amniotic debris. Preterm birth at less than 37 weeks of gestation was more common among women placed on activity restriction (37% compared with 17%, P<.001). After controlling for potential confounding factors, preterm birth remained more common among those placed on activity restriction (adjusted odds ratio 2.37, 95% confidence interval 1.60-3.53). Results were similar for preterm birth at less than 34 weeks of gestation.
  
  
  CONCLUSIONS
  Activity restriction did not reduce the rate of preterm birth in asymptomatic nulliparous women with a short cervix.
authors.affiliation: From the Departments of Obstetrics and Gynecology, Northwestern University, Chicago, Illinois, The Ohio State University, Columbus, Ohio, University of Texas Medical Branch, Galveston, Texas, Case Western Reserve University-MetroHealth Medical Center, Cleveland, Ohio, University of Alabama at Birmingham, Birmingham, Alabama, Brown University, Providence, Rhode Island, Wayne State University, Detroit, Michigan, University of Texas Southwestern Medical Center, Dallas, Texas, Oregon Health & Science University, Portland, Oregon, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, University of Pittsburgh, Pittsburgh, Pennsylvania, and Medical University of South Carolina, Charleston, South Carolina; the George Washington University Biostatistics Center, Washington, DC; and the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland.
authors.forename: William A
authors.initials: WA
authors.lastname: Grobman
authors.forename: Sharon A
authors.initials: SA
authors.lastname: Gilbert
authors.forename: Jay D
authors.initials: JD
authors.lastname: Iams
authors.forename: Catherine Y
authors.initials: CY
authors.lastname: Spong
authors.forename: George
authors.initials: G
authors.lastname: Saade
authors.forename: Brian M
authors.initials: BM
authors.lastname: Mercer
authors.forename: Alan T N
authors.initials: ATN
authors.lastname: Tita
authors.forename: Dwight J
authors.initials: DJ
authors.lastname: Rouse
authors.forename: Yoram
authors.initials: Y
authors.lastname: Sorokin
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Leveno
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Tolosa
authors.forename: John M
authors.initials: JM
authors.lastname: Thorp
authors.forename: Steve N
authors.initials: SN
authors.lastname: Caritis
authors.forename: J
authors.initials: J
authors.lastname: Peter Van Dorsten
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D015444:Exercise; D005260:Female; D006801:Humans; D011247:Pregnancy; D047928:Premature Birth / Q000209:etiology / Q000517:prevention & control*; D016032:Randomized Controlled Trials as Topic; D017211:Treatment Failure; D002577:Uterine Cervical Diseases / Q000150:complications / Q000628:therapy*; D055815:Young Adult